In the Second World War, most African-American soldiers served in segregated units of battalion size, organizations of 500 to 1000 men that were usually commanded by officers with the rank of lieutenant colonel. There were a few instances where separate companies - units of 100 to 200 or so men that were not part of battalions - in which all of the enlisted men were African-American.

During the Battle of the Bulge, the US Army Services of Supply organized African-American volunteers from service units into segregated infantry platoons. These platoons were attached to all-white infantry companies. However, as soon as the war in Europe ended, the platoons were disbanded and their members were reassigned to segregated companies and battalions.